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import java.util.HashMap;
import java.util.Map;

public class FruitCollector {
    public int totalFruit(int[] fruits) {
        Map<Integer, Integer> map = new HashMap<>();
        int i = 0, j = 0, maxFruits = 0;

        while (j < fruits.length) {
            // Add the current fruit to the map
            map.put(fruits[j], map.getOrDefault(fruits[j], 0) + 1);

            // Shrink once , u can also write for generic k
            if (map.size() > 2) {
                int fruitAtI = fruits[i];
                map.put(fruitAtI, map.get(fruitAtI) - 1);

                if (map.get(fruitAtI) == 0) {
                    map.remove(fruitAtI);
                }
                i++; // Shrink the window
            }
          
/// this check is needed for single shrink approach    
           if(map.size()<=2)
             maxFruits = Math.max(maxFruits, j - i + 1);

            // Move the right pointer
            j++;
        }

        return maxFruits;
    }
}